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24 October 2009 | NewScientist | 27
Comment on these stories at www.NewScientist.com/opinion
What can NASA do to improve?
NASA should have a technology road map:
it doesn’t have a plan saying, “These are the
capabilities we have today, these are the
capabilities we want tomorrow, and how are
we going to get there from here?”
Which cutting-edge technologies should
NASA develop first?
The very first element would be a technology for
the handling and storage of propellant in space .
If we had such a “gas station” it would significantly
change the game in terms of what you could do:
it would let you launch a much more capable,
bigger mission with the same-size launchers. If
you use chemical rockets, you want to be able to
manufacture that propellant at your destination .
That saves a huge chunk of initial mass
because you don’t have to take the propellant
with you to get you back to Earth. Then there’s a
whole bunch of ideas for advanced space
propulsion. An ion engine called VASIMR is a
perfect example.
What surprised you most in your work with
the White House’s Augustine Committee?
We hoped to find a way for NASA to do great and
wonderful things within their current budget but
we really didn’t. And it wasn’t for lack of trying.
Over the long term, if you’re not going to make the
budget go up, and you want to do something
great, you have to lower the fixed costs.
What can NASA do to cut costs?
There was one option which involved relying on
expendable launch vehicles – the Delta IV and
Atlas V rockets – the cost of which would be
shared with the Department of Defense. That
does have the potential to change the fixed
costs of the human space flight programme.
Is NASA still capable of inspiring
achievements like the Apollo moon landings ?
It’s easy to say, and I’ve said it myself, that we just
don’t have the NASA we used to have, so we can’t
do the things we used to do. But whatever is
One minute with...
Jeff Greason
wrong or right with NASA, the quality of the
people isn’t a problem. NASA has really good,
motivated people. One contributing factor could
be that we’re not asking them to do the right job.
But the bigger question is, do we really want to
spend whatever it takes, hundreds of billions of
dollars, all so we can race to plant a flag for reasons
of national pride?
But you don’t think we should discontinue
human space exploration?
I think one of the most important findings that we
made on the Augustine committee is that there is
an underlying reason why we should be doing
human space exploration, which is that we ought
to extend permanent human civilisation beyond
this planet, and that is an incredibly important
human endeavour. Stephen Hawking calls for
moon and Mars colonies. To my mind, I can’t see
why we wouldn’t do it. It’s the only way to create a
future in which humans can live somewhere other
than Earth. Robots will help, but you don’t learn
how to live in places by just sending robots.
Interview by David Shiga
One of the leading lights of the private space industry argues that NASA must keep investing in human space exploration
GA
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PROFILE
Jeff Greason is CEO of XCOR Aerospace and sits
on the US’s Augustine Committee, which reviews
NASA’s plans for human space flight. He spoke at
a recent Space Investment Summit in Boston
grown more slowly than that
of most non-dependent crops.
However, contrary to what we
would expect if pollinators were
in decline, the average yield of
pollinator-dependent crops
has increased steadily during
recent decades, as have those
of non-dependent crops, with
no sign of slowing.
Overall, we must conclude
that claims of a global crisis
in agricultural pollination
are untrue.
Pollination problems may be
looming, though. Total global
agricultural production has kept
pace with the doubling of the
human population during the
past five decades, but the small
proportion of this that depends on
pollinators has quadrupled during
the same period. This includes
luxury foods such as raspberries,
cherries, mangoes and cashew
nuts. The increased production of
these crops has been achieved, in
part, by a 25 per cent increase in
cultivated area in response to
increased demand for them.
This expansion may be
straining global pollination
capacity, for two reasons. Demand
for pollination services has grown
faster than the stock of domestic
honeybees, and the associated
land clearance has destroyed
much of the natural habitat
of wild pollinators.
The accelerating increase
of pollinator-dependent crops
therefore has the potential to
trigger future problems both for
these crops and wild plants. These
problems may grow as decreasing
yields of raspberries, cherries and
the rest prompt higher prices,
stimulating yet more expansion
of cultivation. So although the
current pollination crisis is largely
mythical, we may soon have a real
one on our hands. ■
Marcelo Aizen is a researcher at the
National Scientific and Technical
Research Council of Argentina.
Lawrence Harder is a professor
of pollination ecology at the University
of Calgary in Alberta, Canada